What is a Planet?

By: Mallory Kimble, Vanessa VanScyoc, and Alison Koehler

Our Planet Definition

• We believe a planet must...– A. Must orbit the Sun – B. Rotational period less than 60 Earth

days– C. Must have a low eccentricity (less

than 0.5) – D. Must be within 30 AU’s from the Sun. – E. Must have a diameter larger than

1,000 km across.

If it is not a planet…

If the object in space is not classified as a planet, it will either fall under:

A.) Dwarf planet:• Does not meet all of the requirements of a

planet, but meets at least 2. B.) Small Solar System Bodies: • Anything else in space that is not manmade. C.) Man-made object:• Anything in our Solar System that is not

there naturally ( is man-made).

Based on our definition…

Planets Dwarf Planets

Small Solar

System Bodies

Man-made

Objects

Mercury, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

Venus, Ceres, Pluto, Eris, Huamea, Makemake.

All asteroids, meteoroids, comets, and “natural space junk” inside our Solar System.

ISS, rovers, satellites, and all other man-made objects outside of Earth.

Mean Distance from Sun

0.00000

10.00000

20.00000

30.00000

40.00000

50.00000

60.00000

70.00000

80.00000

Merc

ury

VenusEarth

Mars

Jupiter

Saturn

Uranus

Neptune

Ceres

Pluto

Haumea

Makem

ake Eris

Planets

Mea

n D

ista

nce

fro

m S

un

(A

U)

Orbital Period

0.000

20.000

40.000

60.000

80.000

100.000

120.000

140.000

160.000

180.000

Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune Ceres

Planets

Orb

ital

Per

iod

(E

arth

Yea

rs)

Orbital Period

0.000

100.000

200.000

300.000

400.000

500.000

600.000

Pluto Haumea Makemake Eris

Planets

Orb

ital

Per

iod

(E

arth

Yea

rs)

Rotational Period

0.000

50.000

100.000

150.000

200.000

250.000

300.000

Mercury Venus

Planets

Ro

tati

on

al P

erio

d (

Ear

th D

ays)

Rotational Period Cont

0.000

1.000

2.000

3.000

4.000

5.000

6.000

7.000

Earth Mars Jupiter Saturn Uranus Neptune Ceres Pluto Haumea Makemake Eris

Planets

Ro

tati

on

al P

erio

d

Number of Moons

0

10

20

30

40

50

60

70

Jupiter Saturn Uranus Neptune

Planets

Nu

mb

er o

f M

oo

ns

Number of Moons (Dwarf Planets)

0

1

1

2

2

3

3

4

Ceres Pluto Haumea Makemake Eris

Planets

Nu

mb

er o

f M

oo

ns

Number of Moons

0

1

1

2

2

3

Mercury Venus Earth Mars

Planets

Nu

mb

er o

f M

oo

ns

Diameter of Planets

0

20000

40000

60000

80000

100000

120000

140000

160000

Merc

ury

VenusEarth

Mars

Jupiter

Saturn

Uranus

Neptune

Ceres

Pluto

Haumea

Make

make

Eris

planets

dia

met

er(k

m)

Planets Mass compared to Earth

0.00000

0.20000

0.40000

0.60000

0.80000

1.00000

1.20000

Mercury Venus Earth Mars

Planets

Mas

s (E

arth

=1)

Planet's Mass compared to Earth (2)

0.00000

50.00000

100.00000

150.00000

200.00000

250.00000

300.00000

350.00000

Jupiter Saturn Uranus Neptune

Planets

Mas

s (E

arth

=1)

Dwarf Planets Mass Earth=1

0.00000

0.00050

0.00100

0.00150

0.00200

0.00250

0.00300

Ceres Pluto Haumea Makemake Eris

Planets

mas

s E

arth

=1